This invention relates to flexible drive belts and more particularly to metal V-belt structures having continuous band members to maintain the belt in a continuous loop.
Flexible metal V-belts are comprised of a plurality of drive blocks maintained in a continuous loop by metal bands. The bands are generally disposed in slots opening transverse to the belt. The slots are shaped to prevent band migration from the slot and also to prevent the drive blocks from moving inward relative to the bands. This structure has been used for both fan-folded type assemblies, such as that shown in U.S. Pat. No. 4,581,002 issued Apr. 8, 1986, to Cataldo, as well as a more well-known "Van Doorne" type belt.
It has been proposed in the prior art to provide a single set of centrally disposed continuous bands to maintain the belts in a continuous loop. In these arrangements, the bands are disposed in a central slot which opens outwardly. The slot is either completely closed by a pin, such as that shown in U.S. Pat. No. 4,080,841 issued Mar. 21, 1978, to Vollers, or by displacing metal fingers after assembly to capture the bands, as seen in U.S. Pat. No. 4,386,921 issued June 7, 1983, to Roberts, or by designing the slot shape to require flexing of the bands about the longitudinal axis at assembly, as seen in U.S. Pat. No. 4,465,469 issued Aug. 14, 1984, to Cataldo.
Each of these design and assembly techniques has drawbacks. Transverse slots require two sets of bands and accurate profile machining of the slot structure. The other assembly techniques require additional time and/or metal to complete the assembly.